Described herein are pre-dynamic and dynamic cross-linked polymer compositions, and in particular, to methods of making pre-dynamic and dynamic cross-linked polymer compositions.
Previously-described methods of making a dynamic cross-linked polymer composition by combining epoxides and carboxylic acids in the presence of a transesterification catalyst required feeding all components of the polymer into a vessel which was then heated to the processing temperature of the polymer. Once all the starting components were molten, the blend was mixed. During mixing, the cross-linking reaction would take place, which led to an increase in viscosity. While this method is suitable for some small-scale operations, it is cumbersome for larger scales due to difficulties in cleaning the reaction vessels and the stirring implements. In addition, this method does not readily allow for the production of pellets or other forms of material that can be re-worked, for example, by injection molding or profile extrusion.
There accordingly remains a need in the art for methods of making dynamic cross-linked polymer compositions that can be performed on larger scales and that enable pellet formation. It would be a further advantage if dynamic cross-linked polymer compositions could be used in injection molding, profile extrusion processes, and other processes.